I propose to evaluate the function and evolution of multimodal signals across a jumping spider genus. My studies will develop our understanding of sensory integration and multimodal communication at multiple levels of analysis. (1) I will document the function of multimodal signaling in different species of spiders that use multimodal signaling to varying degrees by evaluating male multimodal displays and female choice based on these traits; (2) I will measure the strength of selection on uni- and multimodal traits to test hypothesis on the evolutionary mechanisms driving the evolution of complex signals and multimodal integration; (3) I will evaluate and measure the complexity of visual ornaments, dynamic movement displays, and seismic signals and, using phylogenetic techniques, empirically test hypotheses on the evolution of traits and complexity in displays; (4) I will construct a computational model for the evolution of complex character evolution and test hypotheses on increased sensory integration and species diversification; (5) I will examine hypotheses on constraints in signals. Using measurements of complexity, I will use information theory to estimate constraints on the information content of displays and then use phylogenetic analyses to test whether constraints drive the evolution of multimodal signals. This proposed project will provide important key components to understanding sensory integration in animals and will guide research into uncovering fundamental mechanisms underlying sensory processing and communication. How nervous systems integrate sensory integration is key to understanding how the brain controls behaviour. While the majority of work has focused on elucidating the molecular and cellular mechanisms underlying this process, I approach this question by taking a comparative evolutionary approach. Using modern day techniques in evolutionary biology combined with computational techniques in information theory, this research will provide insights into the processes that drive the integration of multiple inputs which will, in turn, guide the analysis of neural function to uncover fundamental mechanisms underlying sensory integration and communication. [unreadable] [unreadable] [unreadable]